/*******************************************************************************
 * Copyright 2017 Bstek
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License.  You may obtain a copy
 * of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations under
 * the License.
 ******************************************************************************/
package com.bstek.ureport.expression.function;

import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.Date;
import java.util.List;

import com.bstek.ureport.Utils;
import com.bstek.ureport.build.BindData;
import com.bstek.ureport.build.Context;
import com.bstek.ureport.definition.Order;
import com.bstek.ureport.exception.ReportComputeException;
import com.bstek.ureport.expression.model.data.BindDataListExpressionData;
import com.bstek.ureport.expression.model.data.ExpressionData;
import com.bstek.ureport.expression.model.data.ObjectExpressionData;
import com.bstek.ureport.expression.model.data.ObjectListExpressionData;
import com.bstek.ureport.model.Cell;

/**
 * @author Jacky.gao
 * @since 2017年1月21日
 */
public class OrderFunction implements Function {

	@Override
	public Object execute(List<ExpressionData<?>> dataList, Context context, Cell currentCell) {
		if (dataList == null || dataList.size() != 2) {
			throw new ReportComputeException("Function [order] need two parameters");
		}
		boolean result = computeOrder(dataList);
		Order orderData = Order.asc;
		if (!result) {
			orderData = Order.desc;
		}
		final Order order = orderData;
		ExpressionData<?> firstData = dataList.get(0);
		if (firstData instanceof ObjectListExpressionData) {
			ObjectListExpressionData data = (ObjectListExpressionData) firstData;
			List<?> list = data.getData();
			Collections.sort(list, new Comparator<Object>() {
				@Override
				public int compare(Object data1, Object data2) {
					return doOrder(data1, data2, order);
				}
			});
			return list;
		} else if (firstData instanceof BindDataListExpressionData) {
			BindDataListExpressionData bindDataList = (BindDataListExpressionData) firstData;
			List<BindData> list = bindDataList.getData();
			List<Object> ls = new ArrayList<Object>();
			for (BindData bindData : list) {
				Object obj = bindData.getValue();
				if (obj != null) {
					ls.add(obj);
				}
			}
			Collections.sort(ls, new Comparator<Object>() {
				@Override
				public int compare(Object data1, Object data2) {
					return doOrder(data1, data2, order);
				}
			});
			return ls;
		} else {
			return firstData.getData();
		}
	}

	private int doOrder(Object data1, Object data2, Order order) {
		if (data1 == null || data2 == null) {
			return 1;
		}
		if (data1 instanceof Date) {
			Date d1 = (Date) data1;
			Date d2 = (Date) data2;
			if (order.equals(Order.asc)) {
				return d1.compareTo(d2);
			} else {
				return d2.compareTo(d1);
			}
		} else if (data1 instanceof Number) {
			BigDecimal n1 = Utils.toBigDecimal(data1);
			BigDecimal n2 = Utils.toBigDecimal(data2);
			if (order.equals(Order.asc)) {
				return n1.compareTo(n2);
			} else {
				return n2.compareTo(n1);
			}
		} else {
			String str1 = data1.toString();
			String str2 = data2.toString();
			if (order.equals(Order.asc)) {
				return str1.compareTo(str2);
			} else {
				return str2.compareTo(str1);
			}
		}
	}

	private boolean computeOrder(List<ExpressionData<?>> dataList) {
		boolean order = false;
		ExpressionData<?> secondData = dataList.get(1);
		if (secondData instanceof ObjectExpressionData) {
			ObjectExpressionData data = (ObjectExpressionData) secondData;
			Object obj = data.getData();
			if (obj == null) {
				throw new ReportComputeException("Function [order] second parameter can not be null");
			}
			if (obj instanceof Boolean) {
				order = (Boolean) obj;
				return order;
			}
			if (obj instanceof String) {
				order = Boolean.valueOf(obj.toString());
			} else {
				throw new ReportComputeException("Function [order] second parameter muse be boolean type.");
			}
		}
		return order;
	}

	@Override
	public String name() {
		return "order";
	}
}
